Large radial dimensions of helicopter rotor assemblies and the blades associated therewith result in helicopters having large structural envelopes that occupy an inordinate amount of space. It is often desirable to reduce the large structural envelopes of such helicopters to facilitate rapid deployment, routine transport, stowage, and/or to reduce vulnerability of the helicopters to environmental conditions.
One current option available to reduce the structural envelopes associated with helicopters is to design main rotors of helicopters so that main rotor blades may be temporarily removed from a rotor hub assembly (i.e., a main rotor assembly). However, main rotors may be unnecessarily complex, and/or removal of the main rotor blades may be time consuming and labor intensive. Moreover, the same time constraints and labor requirements also exist when the helicopter is reconfigured for subsequent flight operations. Further, a problem exists in this configuration in that removal of the main rotor blades may require a rebalancing of the blades upon reattachment.
Another option often used to reduce the structural envelopes of helicopters is to design main rotor assemblies and rotor blades so that the main rotor blades may be folded about the main rotor assembly. However, no such configuration is currently available because of unique requirements associated with rigid rotor assemblies.
Therefore a rigid rotor assembly is needed that allows main rotor blades to be folded (e.g., rotated) from a deployed position to a stowed position without a need for additional ground support equipment or a removal of any of the main rotor blades.